Embodiments of the present invention generally relate to hanging a variety of items using a clamping device, and more specifically, to a clamping device for safely retaining a jumper during the repair and/or maintenance of electrical transmission and distribution lines.
Electrical power distribution and transmission grids (the “grid”) contain myriad components, including but not limited to wires (i.e., conductors), insulators, switches, and transformers. Most of these components must be serviced on a regular basis, and replaced when necessary, preferably without interrupting the flow of electricity. Working on live electrical wires requires extreme care and specialized tools to prevent, for example, electrocution of the lineman, shorting of the wire, or damage to grid components and surrounding property.
Repairs are often carried out using a length of wire, or conductor, to bypass an area of the grid that needs to be repaired or maintained (the “repair area”). Installation of this wire, or “jumper,” enables electricity flowing through the grid to flow around the repair area, which, in turn, enables the conductor or other components in the repair area to be removed from the circuit for repair or replacement. The jumper can comprise a length of wire sufficiently long to span the repair area and of sufficient gauge to carry the voltage and current present on that portion of the grid. Due to the voltage and current present on the grid, however, the jumper generally comprises a very heavy gauge wire, which represents significant weight that must be supported during repairs.
Conventionally, the jumper is supported using a length of rope, which the lineman simply ties around the jumper and then ties to a nearby conductor, or power line, for support. Unfortunately, ropes are difficult to tie given the heavy gloves worn by linemen and can be tied improperly, both of which can cause the jumper to fall possibly causing personal injury or property damage. If the jumper falls, it can, among other things, electrocute the lineman, damage his truck and equipment, or damage property in the vicinity of the repair area.
In addition, ropes are often not electrically rated (i.e., rated for their resistance to the flow of electricity), which means linemen have no information on which to base their choice of rope. Ropes that are electrically rated typically rated only for their initial use, with their electrical rating decreasing with subsequent each use. This means that rated ropes must be replaced after each use, or represent a similar unknown to unrated ropes after their initial use.